Abstract

Since early this century one of the fundamental goals of organic chemistry has been to understand the molecular basis of enzyme action (1). These protein molecules are the machines of the cell, catalyzing essentially all of the chemical reactions in the biological world. The action of enzymes is characterized by extraordinary specificity and by the ability to effect, in aqueous solvent and at normal temperatures, chemical transformations that are otherwise imperceptibly slow. Early approaches to the study of enzymes involved the laborious and painstaking isolation of pure molecules from biological sources, such as tissue homogenates. Only indirect methods, such as selective chemical modification of amino acid side chains, could be used to study the functional imperatives of the protein molecule itself. Consequently, much more was known about the (usually low MW) substrates than about enzymes themselves.